Unloader tube latching mechanism

ABSTRACT

An unloader tube latching mechanism that automatically hooks when the unloader tube is swung into the discharge position. The latching mechanism includes an overcenter locking device for positively securing the unloader tube in the discharge position.

llnlte States Patent 1 1 9 3 Howell et a1. 1Marcl1 20, 1973 [54] UNLOADER TUBE LATCHING [5 6] References Cited MECHANISM UNITED STATES PATENTS [75] inventors: Elvin L. Howell, James Corwlth,

130th of Bettendorf, [0W3 3,550,793 12/1970 Davidow et a1 ..214/83.32 X 3,279,559 10/1966 Hirst, Jr ..292/97 X [73] Asslgneez International Harvester Company,

Chlcago Primary Examiner-Albert J. Makay [22] Filed: June 18', 1971 Attorney-Floyd B. Harman 21 Appl.No.: 154,541 [57] ABSTRACT An unloader tube latching mechanism that automati- [52] CL gg cally hooks when the unloader tube is swung into the [51] Im- CL B60p U40 discharge position. The latching mechanism includes 58 Field or's;Riff.111111111151 i/'l'' s.26, 522- an mercemer locking device for Positively Securing the unloader tube in the discharge position.

9 Claims, 5 Drawing Figures PATEHTFUHARZOIQYS L 9 sum 10F 2 JAMES CORW/ TH ELV/N L. HOWELL Via/m4 PATENIEDmaonr 3 7 1,359

SHEET ESP 2 I so 62,

UNLOADER TUBE LATCHING MECHANISM BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates generally to a materialhandling apparatus and more particularly to the mounting and latching mechanism for the unloading tube of a combine harvester.

2. Description of the Prior Art Harvesting machines, such as combines, include a grain tank which temporarily stores the harvested grain. The grain tank is provided with an unloader tube through which the grain can be transferred from the grain tank to a truck or other collecting vehicle that has been positioned alongside the combine. The transfer of grain from the grain tank to the collecting vehicle is often done with the combine and collecting vehicle moving in parallel paths without interrupting the harvesting process. In order to facilitate transferring the grain from the grain tank, the unloader tube must be of considerable length and must, when in its discharge position, project away from the combine. When transferring the combine, for example through gates and over highways, it is, of course, undesirable to have the unloader tube protruding outwardly therefrom. For this reason, it has been the standard practice in this art to mount the unloading tubes, such that for transport, it can be folded into a transport position within the confines of the combine. Combines having foldable discharge tubes, such as this, are shown in the patents to Welty U.S. Pat. No. 2,022,166 and Kill U.S. Pat. No. 2,616,579. In the prior art devices, it has been necessary for the combine operator to swing the unloader tube into its discharge position and to then manually engage a latch to thus secure the tube in this position. Since grain is fed through the unloader tube, it is important that this connection is secure and that there is no cracks or gaps through which grain can be lost. Grain loss at this juncture has been a problem in some of the prior art devices.

SUMMARY OF THE INVENTION The present invention provides a latching mechanism for an unloading tube that is automatically booked as the unloading tube is swung into the discharge position. The latching mechanism includes a handle that can be grasped by the operator and pivoted through approximately 90 thus engaging a cam and cam follower which pulls the unloader tube into a secured and sealed position. In pivoting the handle into the secured and sealed position, an overcenter linkage mechanism is used to thus lock the handle in this position. Thus, through this invention, when the unloader tube is swung from its transport position to its discharge position, it is automatically hooked into the latter position. It is not necessary for the operator to manually align or insert any latching pins or bolts. Through this invention, after the unloader tube has been hooked in the discharge position, the operator merely pivots the handle and thus cams the latching mechanism to thus securely seal the unloader tube in its discharge position. There are no special tools required in this operation and there are no pieces or parts that can become misplaced or lost.

It is an object of the present invention to provide a latching mechanism for an unloader tube that is automatically hooked when the unloader tube is swung into the discharge position. It is a further object of this invention to provide a latching mechanism for an unloader tube that will tightly hold the unloader tube in a secured discharge position.

BRIEF DESCRIPTION OF THE DRAWING FIG. ll shows a side view of a combine with the unloader tube in the transport position;

FIG. 2 is an enlarged view of the latching mechanism as the unloader tube approaches its discharge position;

FIG. 3 is an enlarged view of the unloader tube with the latching mechanism in the hooked position;

FIG. 4 is an enlarged view of the latching mechanism in the secured position; and

FIG. 5 is a cross sectional view taken along lines 55 of FIG. 4.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring now to the drawings wherein like reference characters designate like or corresponding parts throughout the several views, there is shown in FIG. 1 a combine designated 10 having drive wheels ll, steerable wheels 12, an operators cab 13, a platform 14, and a grain tank 15. Thegrain tank llS has a discharge tube 20 that is shown in FIG. 1 in the transport or trailing position.

The discharge tube 20 includes a first discharge conveyor housing 21 that is secured to the grain tank about a discharge opening formed therein. The first discharge conveyor housing 211 has an outer terminal end 22 that has a flat sealing face 23 arranged normal to its longitudinal extent. A second discharge conveyor housing 24 is connected by a hinge 28 to the first discharge conveyor housing 21. Hinge 28 has a generally vertically extending axis. The second discharge conveyor housing 24 has an inner terminal end 25 and a discharge end 27. The inner terminal end 25 has a flat sealing face 26 that corresponds in shape and size to the flat sealing face 23 of the outer terminal end 22 such that when the faces 23 and 26 are held in contact with each other they provide a seal through which grain cannot pass.

A cooperating latching means generally designated 30 is provided to secure the discharge tube 20 in its discharge position. The latching means 30 includes a cam pin 31 that is secured to and protrudes outwardly from the outer terminal end 22 of the first discharge conveyor housing 21. A cooperating hitching means carried by the second discharge conveyor housing 24 includes a generally C-shaped hook member 40 that is supported by a pivot mounting 41 at the inner terminal end 25. Hook member 40 has a pivoting cam follower edge 42 that cooperates with the cam pin 31 as seen in FIG. 2 for a purpose that shall be further discussed. Hook member 40 further includes a locking cam follower edge 43 that cooperates with cam pin 31 as shown in FIGS. 3 and 4 for a purpose that shall be further discussed.

The cooperating latching means 30 further includes a mounting or guide plate that is secured by nuts and bolts 71 to the second discharge conveyor housing 24. It should be noted that the guide plate 70 is shaped such that its major portion is spaced away from the second discharge conveyor housing. A handle 50 is carried by the guide plate 70 by a pivot mounting 51 that includes a spring friction washer 52 located between the handle and guide plate 70 and a lock nut 53 located on the undersurface of the guide plate 70. See FIG. 5.

A link member 60 operatively connects the handle 50 to the hook member 40. One end of link member 60 is secured to the hook member 40 by a pivot connection 64 and the other end is joined to the handle 50 by a pivot connection 65. The link member 60 is fabricated from a clevis 61 that is threaded to receive a threaded rod 62. The threaded portions of rod 62 and clevis 61 provide an adjustment through which the desired overcenter clamping pressure can be obtained in the discharge position. As best seen in FIG. 5, the unthreaded end of rod 62 is offset and functions as a guide means 63.

An arcuate groove 72 is formed in guide plate 70 having as a center the pivot axis of handle 50. The radius of arcuate groove 72 corresponds to the distance between the pivot axis of handle 70 and the pivot axis of the pivotable connection 65 of link member 60 to the handle 50. As illustrated herein, arcuate groove 72 extends slightly over 90 and one end forms a first stop means 73 and the other end forms a second stop means 74. As can be best seen in FIG. 5, the guide means 63 extends through the arcuate groove 72 and engages first and second stop means 73 and 74 to thus limit the pivotable movement of handle 50.

OPERATION When the discharge tube is in the transport position as shown in FIG. 1, handle 50 is pulled to its forwardmost position at which the guide means 63 engage the first stop means 73. The handle 50 is retained in this position by the spring friction washer 52. With the handle 50 so located, the pivoting cam follower 42 is positioned to engage the cam pin 31 when the discharge tube 20 is swung from the transport position of FIG. 1 towards its discharge position. As can be best seen in FIG. 2, upon swinging the second discharge conveyor housing 24 further so that the flat sealing faces 23 and 26 are in engagement, it will cause the hook member 40 to pivot about its pivot mounting 41 in a clockwise direction. Thus resulting in a relationship as shown in FIG. 3. FIG. 3 represents the hook relationship of the latching means 30. As seen in FIG. 3, the hook member 40 has been hooked around the cam pin 31 and the beak portion 44 as well as the spring friction washer 52 function to hold the latching means in this position. Thus by swinging the discharge tube 20 from the transport position to the discharge position, it is automatically hooked in the latter location. As can be seen in FIG. 3, the flat sealing faces 23 and 26 are not flush to each other and thus grain could be lost through the opening. As seen in FIG. 3, cam pin 31 is in engagement with locking cam follower 43 of the hook member 40. Upon pivoting handle 50 counterclockwise from its position of FIG. 3 to its position of FIG. 4, locking cam follower 43 slides up cam pin 31 thus pulling the second discharge conveyor housing into a secured position relative to the first discharge conveyor housing. As shown in FIG. 4, in this secured position, the flat sealing faces 23 and 26 are flush with each other and have thus produced a grain impermeable seal between the first and second housings. As seen in FIG. 4, handle 50 is in a position at which the guide means 63 are in engagement with the second stop means 74. It should be noted that in this position, the centerline of threaded rod 62 has passed over the pivot axis of handle 50 and is thus in an overcenter lock position. As handle 50 is pivoted counterclockwise from the position shown in FIG. 3 towards the position shown in FIG. 4, it causes hook member 40 to pivot about its pivot mounting 41 in a clockwise direction up to the point where the centerline of threaded rod 62 coincides with the pivot axis of handle 50. As handle 50 is pivoted counterclockwise beyond this point, it causes an opposite or counterclockwise rotation of hook member 40. Thus, once the handle 50 reaches the position shown in FIG. 4, it resists clockwise rotation because this requires the locking cam follower 43 to ride up or tighten relative to the cam pin 31 and it cannot move further in the counterclockwise direction because guide means 63 is in engagement with the second stop means 74. Thus, a positive pressure must be applied to handle 50 in a clockwise direction to move it from the position of FIG. 4 to the position of FIG. 3. This positive pressure is applied when it is desired to swing the discharge tube 20 from its discharge position to its transport position.

What is claimed is:

1. In a mobile material-handling apparatus including a first discharge conveyor housing having an outer terminal end;

a second discharge conveyor housing having an inner terminal end;

said second housing being hinged at said inner terminal end to said outer terminal end of said first housing such that it is adapted to swing between an end-to-end operative relationship and an angular transport relationship;

cooperating latch means carried by said by outer and inner terminal ends, said latch means including a cam pin secured to and protruding outwardly from said first discharge conveyor housing, a hook member pivotally mounted on said second housing, said hook member including a pivoting cam follower that is adapted to contact said cam pin when said second housing approaches the end-toend operative relationship, continued contact between said pivoting cam follower and said cam pin as said second housing swings towards the endto-end operative relationship causes said hook member to pivot about its mounting and assume said hooked position relative to said cam pin, said hook member including a locking cam follower adapted to engage said cam pin when said latching means is in the hooked position and operative upon further pivoting of said hook member to swing said second discharge conveyor housing to a secured position;

said latch means including a handle operatively connected to said hook member that can be manipulated by an operator to move said latch means from the hooked position to the secured position or from the hooked or secured position to an unlatched position.

2. The invention as set forth in claim 1, wherein said handle is pivotally mounted on said second housing and is operatively connected to said hook member by a link member pivotally connected at one end to said handle and at the other end to said hook member.

said handle and adapted to slide in said arcuate groove to restrict pivotable movement of the handle to the confines of said arcuate groove, said first stop means being located such that when the handle is positioned to correspond thereto said hook member is positioned such that the pivoting cam follower will engage the cam pin as said second housing is swung towards the end-toend operative relationship.

4. The invention as set forth in claim 2, wherein the pivotable mounting of said handle includes a spring friction washer to hold it in a selected position.

5. The invention as set forth in claim 2, wherein a guide plate is mounted on said second housing adjacent the pivot mounting of said handle, an arcuate groove formed in said plate of a radius corresponding to the distance between the pivotable mounting of said handle and the pivotable connection of said link member to said handle, said arcuate groove formed about the pivotable mounting of said handle, said arcuate groove being of an explicit length such that the ends define first and second stop means, guide means carried by said handle and adapted to slide in said arcuate groove to restrict pivotable movement of the handle to the confines of said arcuate groove, said second stop means being located such that when the handle is positioned to correspond thereto said link member has moved over the handles pivot mounting to an overcenter locked position.

6. The invention as set forth in claim 5, wherein said first stop means is located such that when the handle is positioned to correspond thereto said hook member is positioned such that the pivoting cam follower will engage the cam pin as said second housing is swung toward the end-to-end operative relationship.

7. The invention as set forth in claim 4, wherein a guide plate is mounted on said second housing adjacent the pivot mounting of said handle, an arcuate groove formed in said guide plate of a radius corresponding to the distance between the pivotable mounting of said handle and the pivotable connection of said link member to said handle, said arcuate groove formed about the pivotable mounting of said handle, said arcuate groove being of an explicit length such that the ends define first and second stop means, guide means carried by said handle and adapted to slide in said arcuate groove to restrict pivotable movement of thehandle to the confines of said arcuate groove, said first stop means beingvlocated such that when the handle is positioned to correspond thereto said hook member is positioned such that the pivoting cam follower will engage the cam pin as said second housing is swung toward the end-to-end operative relationship.

8. The invention as set forth in claim 4, wherein a guide plate is mounted on said second housing adjacent the pivot mounting of said handle, an arcuate groove in said plate of a radius corresponding to the distance between the pivotable mounting of said handle and the pivotal connection of said link member to said handle, said arcuate groove formed about the pivotable mounting of said handle, said arcuate groove being of an explicit length such that the ends define first and second stop means, guide means carried by said handle and adapted to slide in said arcuate groove to restrict pivotal movement of the handle to the confines of said arcuate groove, said second stop means being located such that when the handle is positioned to correspond thereto said link member has moved over the handle pivot mounting to an overcenter lock position.

9. The invention as set forth in claim 8, wherein said first stop meansis located such that when the handle is positioned to correspond thereto said hook member is positioned such that the pivoting cam follower will engage the cam pin as said second housing is swung toward the end-to-end operative relationship. 

1. In a mobile material-handling apparatus including a first discharge conveyor housing having an outer terminal end; a second discharge conveyor housing having an inner terminal end; said second housing being hinged at said inner terminal end to said outer terminal end of said first housing such that it is adapted to swing between an end-to-end operative relationship and an angular transport relationship; cooperating latch means carried by said by outer and inner terminal ends, said latch means including a cam pin secured to and protruding outwardly from said first discharge conveyor housing, a hook member pivotally mounted on said second housing, said hook member including a pivoting cam follower that is adapted to contact said cam pin when said second housing approaches the end-to-end operative relationship, continued contact between said pivoting cam follower and said cam pin as said second housing swings towards the end-to-end operative relationship causes said hook member to pivot about its mounting and assume said hooked position relative to said cam pin, said hook member including a locking cam follower adapted to engage said cam pin when said latching means is in the hooked position and operative upon further pivoting of said hook member to swing said second discharge conveyor housing to a secured position; said latch means including a handle operatively connected to said hook member that can be manipulated by an operator to move said latch means from the hooked position to the secured position or from the hooked or secured position to an unlatched position.
 2. The invention as set forth in claim 1, wherein said handle is pivotally mounted on said second housing and is operatively connected to said hook member by a link member pivotally connected at one end to said handle and at the other end to said hook member.
 3. The invention as set forth in claim 2, wherein a guide plate is mounted on said second housing adjacent the pivot mounting of said handle, an arcuate groove formed in said guide plate of a radius corresponding to the distance between the pivotable mounting of said handle and the pivotal connection of said link member to said handle, said arcuate groove formed about the pivotable mounting of said handle, said arcuate groove being of an explicit length such that the ends define first and second stop means, guide means carried by said handle and adapted to slide in said arcuate groove to restrict pivotable movement of the handle to the confines of said arcuate groove, said first stop means being located such that when the handle is positioned to correspond thereto said hook member is positioned such that the pivoting cam follower will engage the cam pin as said second housing is swung towards the end-to-end operative relationship.
 4. The invention as set forth in claim 2, wherein the pivotable mounting of said handle includes a spring friction washer to hold it in a selected position.
 5. The invention as set forth in claim 2, wherein a guide plate is mounted on said second housing adjacent the pivot mounting of said handle, an arcuate groove formed in said plate of a radius corresponding to the distance between the pivotable mounting of said handle and the pivotable connection of said link member to said handle, said arcuate groove formed about the pivotable mounting of said handle, said arcuate groove being of an explicit length such that the ends define first and second stop means, guide means carried by said handle and adapted to slide in said arcuate groove to restrict pivotable movement of the handle to the confines of said arcuate groove, said second stop means being located such that when the handle is positioned to correspond thereto said link member has moved over the handle''s pivot mounting to an overcenter locked position.
 6. The invention as set forth in claim 5, wherein said first stop means is located such that when the handle is positioned to correspond thereto said hook member is positioned sucH that the pivoting cam follower will engage the cam pin as said second housing is swung toward the end-to-end operative relationship.
 7. The invention as set forth in claim 4, wherein a guide plate is mounted on said second housing adjacent the pivot mounting of said handle, an arcuate groove formed in said guide plate of a radius corresponding to the distance between the pivotable mounting of said handle and the pivotable connection of said link member to said handle, said arcuate groove formed about the pivotable mounting of said handle, said arcuate groove being of an explicit length such that the ends define first and second stop means, guide means carried by said handle and adapted to slide in said arcuate groove to restrict pivotable movement of the handle to the confines of said arcuate groove, said first stop means being located such that when the handle is positioned to correspond thereto said hook member is positioned such that the pivoting cam follower will engage the cam pin as said second housing is swung toward the end-to-end operative relationship.
 8. The invention as set forth in claim 4, wherein a guide plate is mounted on said second housing adjacent the pivot mounting of said handle, an arcuate groove in said plate of a radius corresponding to the distance between the pivotable mounting of said handle and the pivotal connection of said link member to said handle, said arcuate groove formed about the pivotable mounting of said handle, said arcuate groove being of an explicit length such that the ends define first and second stop means, guide means carried by said handle and adapted to slide in said arcuate groove to restrict pivotal movement of the handle to the confines of said arcuate groove, said second stop means being located such that when the handle is positioned to correspond thereto said link member has moved over the handle pivot mounting to an overcenter lock position.
 9. The invention as set forth in claim 8, wherein said first stop means is located such that when the handle is positioned to correspond thereto said hook member is positioned such that the pivoting cam follower will engage the cam pin as said second housing is swung toward the end-to-end operative relationship. 